Fourteen years ago, the blunted, Eastern-tinged beats of DJ Krush's debut album on James Lavelle's Mo' Wax label, Strictly Turntablized, introduced us to the mysterious and seductive world of Japanese hip-hop. Alongside his fellow Mo' Wax "crate digger" DJ Shadow, Tokyo-born Krush personified the nerdish vinyl junkie who delights in ploughing through thousands of records searching for myriad elements to reconfigure into beatific, instrumental hip-hop. The pair catapulted James Lavelle's record label to cult status, pioneered the concept of turntables as instruments that could be "played", and redefined what hip-hop could be.
In today's digital global village, Brazilian, Angolan and South African hip-hop can be accessed in seconds, and music exists as intangible digital files. Vinyl now seems quaint and anachronistic, so perhaps nostalgia and sentimentality are part of the attraction for this show. Koko is heaving: the venue's balconies, spread over six tiers, are teeming with international hip-hop connoisseurs jealously guarding their vantage points of the stage. It's probably the most varied collection of retro tracksuit tops gathered under one roof, mirroring Krush's old-school-b-boy stylings: baseball cap, baggy jeans and over-sized white T-shirt with a crimson disc, representing the Japanese flag.
Krush (real name Hideaki Ishii), uses the classic DJ set-up of two turntables and a mixer that's been a hip-hop staple since Kool DJ Herc's Bronx block parties 30 years ago. Except that he has no record box – all the materials for tonight's gig are stored on a laptop and relayed to blank vinyl, a happy medium between digital and analogue.
Krush commits stylus to wax and a vocodered voice announces: "Hello everybody in London, welcome to DJ Krush". He seizes the moment and whips up an unsettling, brooding storm by scratching, shredding and distorting howling winds and wailing sirens. After what seems like an eternity (five minutes), a chugging beat balms the dancefloor's itchy feet. Soaring strings dance over this slowly unfurling mini-symphony and suck you into a meditative soundscape. This is music to get lost in – shut your eyes, head-nod and be transported to another dimension (it wasn't dubbed "trip-hop" for nothing).
The necessity of holding the vast, raucous audience's attention, though, means that Krush's live journey isn't as winding or deep as it has been previously. He veers towards Mr Scruff territory as jaunty brass and drunken horns meet swinging ragtime. On record, Krush is a visual experience, but tonight it's more of a physical experience, with occasionally mesmerising moments. There's lots of dancing. He punctures one period of hypnotic, drifting ambience with the title track of his 1996 album, Meiso, which features The Roots' rappers Black Thought and Malik B (aside from the intro, it's the only vocal in the set). Krush then delivers a virtuoso turntablist solo, chopping, scratching and kneading a piece of free-jazz drumming, first into a lumbering, off-kilter rhythm, and then into skittering drum'*'bass.
He doesn't look up once all night, a picture of studied concentration, constantly fidgeting, tweaking, nudging and adjusting his mixer, or teasing the cross fader with one hand while the other bends the vinyl to his will. He brings the transfixed beat zombies to life with his signature record (his first on Mo' Wax), 1994's Kemuri. Its horns, sirens, Eastern strings, skidding rhythms and noirish, melancholy mood sound as ground-breaking and timeless as ever. And with that, Krush exits, waving apologetically as he hurries off stage; there's not even a nanosecond of basking in wave after wave of adulation, let alone an encore.
There's a sense that the digital revolution has precipitated the decline of the turntable-as-instrument and DJs mixing vinyl records. But with hip-hop the dominant language of today's global youth culture, DJ Krush's postmodern performance – fashioning something entirely new from what already exists – seems as vital and compelling as ever.